The invention relates to high energy, flow-coupling, coil-per-plug inductive ignition systems with high energy density coils, operating at high voltage and current, for use more ideally with internal combustion engines which produce high flow at the spark plug site during ignition. Preferably, the invention relates to a 42 volt based coil-per-plug inductive ignition system as disclosed in my U.S. Pat. No. 6,142,130, referred to henceforth as '130, having high energy density coils of approximately 150 mj and high spark currents in the 200 to 600 ma range, and having a pair of biasing magnets in the open end of the E-core, as has been disclosed, in part, in my PCT patent application No. PCT/US03/12057, referred to henceforth as '057, published as WO 2003/089784 A3 on Oct. 30, 2003. The disclosures of '130 and '057, and other patents and patent applications cited below, are incorporated herein as though set out at length herein.
A central aspect of the present invention is that it has a spark current of approximately 300 ma, an energy of approximately 150 mj, a secondary turns Ns to primary turns Np ratio preferably equal to 60, i.e. Nt is between 53 to 67, where Nt=Ns/Np, and a primary turns Np between 60 and 90. In terms of a special ratio R which I define as Np/Nt, i.e. R≡Np/Nt, then R is greater than 1, and more precisely equal to 1.3, or between 1.15 and 1.45.
The term “approximately” or “approximately equal to” as used throughout this specification means within plus or minus 25% of the value it qualifies and the term “equal to” means plus or minus 12% of the value it qualifies, unless otherwise stated.
An aspect of the present invention is that it can be made to operate predominantly in the glow discharge mode, where 200 ma is the demarcation between the glow and arc. It can operate in the glow discharge mode, even above 200 ma, e.g. 400 ma, by selective use of electrode material, such as stainless steel. An advantage on the glow is that it is more erosion resistant than the arc discharge, and is also a more efficient discharge in low-flow or quiescent flow.